PartsTable TECHNICAL DATA SHEET
JULY 2026Technical Data Sheet

M-20.2Breathing Apparatus,self-Contain

Ocenco Inc · NSN 4240-01-439-5937 · FSC 4240 · No Item Name Available
Verified by PartsTable
NSN 4240-01-439-5937 — this item is cataloged by the U.S. Government under National Stock Number 4240-01-439-5937. Primary manufacturer part number: M-20.2.
Features
  • Breathing Apparatus,self-Contain — FSC 4240
  • Special Test Features: ITEMS ARE BEING CODED AS CRITICAL TO INSURE SOURCE INSPECTION WILL BE PERFORMED AT THE POINT OF MANUFACTURE, PRIOR TO MATERIAL RECEIPT BY THE US NAVY OR OTHER DOD COMPONENTS. THESE ITEMS ARE PIECE PARTS OR END ITEMS IN SUPPORT OF VITAL MILITARY HARDWARE NECESSARY TO SUSTAIN THE SUCCESSFUL MISSION OF THE SHIPS, SUBMARINES, AND SHORE STATIONS OF THE US NAVY. CRITICAL FEATURES INCLUDING, BUT NOT LIMITED TO, DIMENSIONS, TOLERANCES/CLEARANCES, ELECTRONIC CHARACTERISTICS, AND METALLURGICAL PROPERTIES WILL BESPECIFIED FOR GOVERNMENT Q AR (QUALITY ASSURANCE REPRESENTATIVES) TO INSURE THE HIGHEST POSSIBLE DEGREE OF QUALITY AND RELIABILITY OF THESE PARTS BEING DELIVERED UNDER NAVICP CONTRACTS
  • Criticality Code Justification: SPCL
  • 2 verified cross-references
  • Primary manufacturer: Ocenco Inc
Applications
  • Industrial maintenance and repair
  • Government and military logistics
  • Equipment overhaul and refurbishment
General Description

The Breathing Apparatus,self-Contain, cataloged under National Stock Number 4240-01-439-5937, is classified within Federal Supply Class 4240 (No Item Name Available) of the Fire Fighting, Rescue, and Safety Equipment group. The primary manufacturer of record is Ocenco Inc. Government technical data includes 2 verified specifications, sourced from the Federal Logistics Information System (FLIS). This item has 2 commercial cross-references from 2 manufacturers, enabling identification through both NSN and commercial part number lookups. 9 verified substitutes exist in the FLIS interchangeability database. Current acquisition status: Active.

Technical Specifications
ParameterValue
NSN4240-01-439-5937
Primary Part NumberM-20.2
Item NameBreathing Apparatus,self-Contain
FSC / FSG4240 / 42 — No Item Name Available
ManufacturerOcenco Inc
StatusACTIVE
Special Test FeaturesITEMS ARE BEING CODED AS CRITICAL TO INSURE SOURCE INSPECTION WILL BE PERFORMED AT THE POINT OF MANUFACTURE, PRIOR TO MATERIAL RECEIPT BY THE US NAVY OR OTHER DOD COMPONENTS. THESE ITEMS ARE PIECE PARTS OR END ITEMS IN SUPPORT OF VITAL MILITARY HARDWARE NECESSARY TO SUSTAIN THE SUCCESSFUL MISSION OF THE SHIPS, SUBMARINES, AND SHORE STATIONS OF THE US NAVY. CRITICAL FEATURES INCLUDING, BUT NOT LIMITED TO, DIMENSIONS, TOLERANCES/CLEARANCES, ELECTRONIC CHARACTERISTICS, AND METALLURGICAL PROPERTIES WILL BESPECIFIED FOR GOVERNMENT Q AR (QUALITY ASSURANCE REPRESENTATIVES) TO INSURE THE HIGHEST POSSIBLE DEGREE OF QUALITY AND RELIABILITY OF THESE PARTS BEING DELIVERED UNDER NAVICP CONTRACTS
Criticality Code JustificationSPCL
Lifecycle & Compliance
Acquisition StatusACTIVE
HAZMATNo
Verified Substitutes 9
3110-00-155-67100042970 INTERCHANGEABLE
Bearing,ball,annular
New Holland Construction
3110-00-159-9071102668-623 INTERCHANGEABLE
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Army, United States Department of the Dba Watervliet Arsenal Div Business Development
5910-00-712-88598386442 INTERCHANGEABLE
Capacitor Feed-Thru Connector
U S Army Tank Automotive Command Amsta-Im-Mm
6635-01-102-8042M202 INTERCHANGEABLE
Transducer,ultrasonic Flaw Detec
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5945-01-115-5171M-202 INTERCHANGEABLE
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C & H Machine Inc Dba Support Equipment Inc.
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Cross-Reference Index
Part NumberManufacturer
10065840 Nimikkeistokeskus Ncb Finland (FIN)
M-20.2 PRIMARY Ocenco Inc (USA)
Related Parts
3110-00-155-6710INTERCHANGEABLE
BEARING,BALL,ANNULAR
0042970
3110-00-159-9071INTERCHANGEABLE
BEARING,BALL,ANNULAR
102668-623
6145-00-508-4709INTERCHANGEABLE
CABLE,POWER,ELECTRICAL
8770496
5910-00-712-8859INTERCHANGEABLE
CAPACITOR FEED-THRU CONNECTOR
8386442
6635-01-102-8042INTERCHANGEABLE
TRANSDUCER,ULTRASONIC FLAW DETEC
M202
5945-01-115-5171INTERCHANGEABLE
SOLENOID,ELECTRICAL
M-202
4320-01-129-5277INTERCHANGEABLE
PUMP,FLUID SERVICE
M202
6650-01-382-7842INTERCHANGEABLE
EYEPIECE,MICROSCOPE
M202
5963-01-544-3489INTERCHANGEABLE
PRINT SERVER MICROP
M212

Frequently Asked Questions

What is NSN 4240-01-439-5937?

NSN 4240-01-439-5937 is a Breathing Apparatus,self-Contain, manufactured by Ocenco Inc, classified under FSC 4240 (No Item Name Available). Status: active.

What are the part numbers for NSN 4240-01-439-5937?

NSN 4240-01-439-5937 has 2 cross-referenced part numbers: 10065840 (Nimikkeistokeskus Ncb Finland), M-20.2 (Ocenco Inc).

What NSN replaces 4240-01-439-5937?

There are 9 known substitutes for 4240-01-439-5937: 3110-00-155-6710, 3110-00-159-9071, 6145-00-508-4709 and 6 more. Verify interchangeability with system specifications before substitution.

What are the specifications of M-20.2?

Key specifications for M-20.2: Special Test Features: ITEMS ARE BEING CODED AS CRITICAL TO INSURE SOURCE INSPECTION WILL BE PERFORMED AT THE POINT OF MANUFACTURE, PRIOR TO MATERIAL RECEIPT BY THE US NAVY OR OTHER DOD COMPONENTS. THESE ITEMS ARE PIECE PARTS OR END ITEMS IN SUPPORT OF VITAL MILITARY HARDWARE NECESSARY TO SUSTAIN THE SUCCESSFUL MISSION OF THE SHIPS, SUBMARINES, AND SHORE STATIONS OF THE US NAVY. CRITICAL FEATURES INCLUDING, BUT NOT LIMITED TO, DIMENSIONS, TOLERANCES/CLEARANCES, ELECTRONIC CHARACTERISTICS, AND METALLURGICAL PROPERTIES WILL BESPECIFIED FOR GOVERNMENT Q AR (QUALITY ASSURANCE REPRESENTATIVES) TO INSURE THE HIGHEST POSSIBLE DEGREE OF QUALITY AND RELIABILITY OF THESE PARTS BEING DELIVERED UNDER NAVICP CONTRACTS; Part Name Assigned by Controlling Agency: EMERGENCY ESCAPE BREATHING DEVICE; Criticality Code Justification: SPCL; Special Features: QUICKLY DONNED IN SECONDS-SIMPLY UNLATCH THE CASE, PULL OUT THE UNIT, AND INSERT THE MOUTHPIECE AND NOSE CLIP; THE ATTACHED HOOD CAN BE DONNED AT ANY TIME DURING THE ESCAPE; CERTIFIED FOR 15 YEARS SERVICE LIFE; MAINTENANCE FREE FOR 15 YEARS-ONLY VISUAL INSPECTIONS BY SHIPBOARD PERSONNEL ONCE EVERY TWO YEARS; THE SEALED WATERTIGHT CASE PROTECTS AGAINST HARST MARINE CONDITIONS;SUPERIOR PERFORMANCE WITH AUTOMATIC ACTIVATION, COMPLETE PROTECTION FROM LIFE THREATENING ATMOSPHERES AND THE HIGHEST RESPIRATORY PROTECTION FACTOR AVAILABLE; TYPICAL PERFORMANCE DURATION IS BETWEEN 15 AND 32 MINUTES. 4 total characteristics are documented in the Federal Logistics Information System.

Validated with multiple authoritative sources, including Government, OEM, and Certified sources.
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